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Cisco Bug: CSCtb79088 - ScEoMPLS traffic blackholed in ES20 when performing label dispostion

Last Modified

Feb 22, 2014

Products (1)

  • Cisco 7600 Series Routers

Known Affected Releases


Description (partial)


Traffic flow is interrupted on ES20 linecard through Xconnect in a EVC under main interface of a ES20. Traffic is received from MPLS core interfaces and is not delivered out of the xconnect.

It's observed when the mpls interface is a subinterface of the same main interface where the broken  EVC is configured.  Something like:

interface GigabitEthernet1/0/1
 service instance <vlan tag> ethernet
  encapsulation dot1q <vlan tag>
  rewrite ingress tag pop 1 symmetric
  xconnect a.b.c.d  xxx  encapsulation mpls

interface GigabitEthernet1/0/1.XXX
 mpls ip


- The same xconnect is working fine for some days afer its configuration.
- Traffic through this xconnect gets broken with no intervention or config change.

Further Problem Description:

traffic counters for:
- show mpls l2transport VC x
- show ethernet service instance id x interface x/y/z

Are displaying increasing counters for both sent and transmit despite that in egress direction no traffic is being forwarded.
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